Derek Jacobi is finally able to shed his old-age make up and play the young Claudius for the first time. Joining him at the start of the episode are several new actors, which means that a Claudius voice over is required in order to explain to the audience exactly who these runners and riders are.

There’s Postumus (John Castle), Marcus Agrippa’s surviving son and Claudius’ best friend, Claudius’ brother Germanicus (David Robb) as well the scheming Livilla (Patricia Quinn). Livilla is married to Castor (Kevin McNally) but spends her time making googly eyes at Postumus. Their illicit affair turns out to be key to the episode ….

Claudius’ isolation from the Imperial family is made clear in this opening scene. He’s allowed to dine with them, but only on a couch that’s placed a discreet distance away. Despite this unspoken segregation, he’s not totally friendless – Postumus is always prepared to stand up for him and even Augustus regards him with a distracted affection.

Before the serious business begins, there’s the joy of watching Augustus interact with the poet Horace (Norman Shelley). Augustus’ puritanical streak emerges (not for the first time) as he regrets the way that some poets delight in recording only the more sordid aspects of life. “Write poetry, yes, but write about nice things – things that you’d like your children to hear”.

Given that the definitive radio Sherlock Holmes (Carlton Hobbs) appeared in episode one, it’s nice that Shelley (Hobbs’ Doctor Watson) also makes an appearance in I Claudius.  Possibly it was just a coincidence, but it might be that director Herbert Wise remembered their decades long partnership and decided to find Shelley a small role.

Brian Blessed is then given the chance to move into high gear as an unbelieving Augustus receives news that three legions have been massacred in Germany. It’s interesting to see how Tiberius reacts to this – unlike Augustus, he’s totally calm and quite prepared to go out there in order to steady the ship.

Donald Eccles and Denis Carey (as Pollio and Livy) both essay decent cameos. A pair of eminent historians, they’re flattered by Claudius’ interest in their work – although Livy is less flattered when Claudius is unable to tell him which of them he prefers! The scene ends on a serious note though, as Pollio – when he’s alone with Claudius – suggests he carries on playing the fool (that way he might just stay alive). It’s worth bearing this in mind when observing some of Claudius’ later clumsy behavior.

What Shall We Do About Claudius? features several lengthy two handed scenes. The first – between Livia and Livilla – sees Livia (as in the previous episode) casually manipulate a hapless individual in order to remove yet another rival (in this case Postumus) to the throne. Livilla is able to emote in an impressive way, although I get the sense that some of her tears are purely for show (she’s wasting her time though – Livia’s not the one to be moved by sentiment).

The following two-hander (a domestic squabble between Augustus and Livia) is also highly entertaining and leads into the games at the Coliseum, which are being held in honour of Drusus. We meet the adult Herod Agrippa (James Faulkner) for the first time and are also given the opportunity to marvel at the set (which gives the impression of great height – helped by some lower than normal camera angles).

I enjoyed Livia’s pep talk to the gladiators. “These games are being degraded by the increasing use of professional tricks to stay alive! And I won’t have it! So put on a good show and there’ll be plenty of money for the living and a decent burial for the dead. And if not? I’ll break this guild up. And I’ll send the lot of you to the mines in Numidia.”

Later, Postumus is falsely accused of rape by Livilia. The Television Centre roof rattles as John Castle and Brian Blessed wring every last drop out of emotion out of the script. I Claudius is a serial packed with memorable moments, but this one has to be right at the top.

Oh grandfather, open your eyes. Over the years everyone you knew and loved has either died or disappeared. Do you think it was all an accident? My father Agrippa, and before him Marcellus, my brothers Gaius and Lucius, my mother Julia – NOW ME.

After this intensity, the episode winds down with Claudius’ long postponed marriage. His unnamed bride turns out to be much taller than he is, which is the cue for hysterical laughter from all the onlookers (even Livia and Claudius’ mother Antonia – two people who never find anything Claudius does even remotely amusing – have a chuckle).

It’s an oddly discomforting and grotesque scene. Possibly because we then cut back to the elderly, drunken Claudius before the credits roll, we should take it to be nothing more than his fevered remembering, rather than real life.