The Tenth Doctor (David Tennant) and professional thief Lady Christina de Souza (Michelle Ryan) are both passengers on a London double decker bus that gets re-routed to a barren alien world. Can they work together to get the bus and its other passengers safely back to Earth? Meanwhile, back on Earth, UNIT is called in to deal with the sudden disappearance of the bus.

As written by outgoing showrunner Russell T Davies and Gareth Roberts (“The Shakespeare Code”, “The Unicorn and the Wasp”), this one hour Easter special is a lighthearted romp with action, comedy, and even some romantic sparks. Director James Strong, a Doctor Who and Torchwood veteran, brings all the elements together into a shiny package of fun. I greatly enjoyed watching it.

Some hints emerge toward the end that darker days are coming for the Doctor. Davies has stated that Tennant’s final three specials, set to air in November and December, will grow increasingly darker, leading to the death of the Tenth Doctor and his regeneration into the Eleventh.

Despite six months away acting on stage, Tennant effortlessly steps back into his most famous role. Ryan, most recently the star of the Bionic Woman remake and the sorceress Nimueh on Merlin, is perfect as a sophisticated and charming adrenaline junkie in the manner of Lara Croft. Lady Christina would make a great ongoing companion. Also good are Noma Dumezweni as UNIT Captain Erisa Magambo, Lee Evans as current UNIT scientific advisor Professor Malcolm Taylor (humorously played as the ultimate fanboy), and Adam James as a police officer pursuing Lady Christina.

Other notes: this episode was filmed on location in Dubai; the bus was damaged in transport to Dubai, but only minor script changes were needed to account for that; it’s the first episode of Doctor Who to be shot on high definition video; by some counting methods it’s the 200th complete story (spread out over 753 individual episodes since 1963); I loved the references to Quatermass and the 1974-75 Fourth Doctor serial, “Robot.”

Next up, “The Waters of Mars” in November.