"Different Worlds - Part Two" is the 544th episode of Casualty and the second episode of the 21st series. It was preceded by "Different Worlds - Part One" and followed by "Waste of Space". The episode was directed by Patrick Lau and written by Ann Marie Di Mambro. It comprises the second half of the 20th anniversary special, and is one hour in length.
Like the first part, this episode takes place in both the emergency department and Cambodia. This episode features another guest appearance of Lisa "Duffy" Duffin, portrayed by Cathy Shipton, who went on to make her next guest appearance almost nine years later in 2015.
The ward is in chaos in the wake of the school bus accident and tensions are running high between Harry and the new doctor, Somnang. However Somnang redeems himself when he shows Harry mobile phone footage of the incident which helps determine a school girl's injuries.
A school boy, Jason, suffers a leg injury. His mother happens to be drunk Grace, who was previously in the department. When their social worker, Maria, is brought in after being attacked, Jason informs Maggie that his mother is the culprit.
Meanwhile, even under traumatic circumstances, Kelsey is determined to play Cupid when she spots an opportunity between the bus driver, Liz, and her friendly neighbour, patient Tommy.
Over in Cambodia, Abs and Comfort help with a difficult birth. They are able to save the newborn but not the mother. Comfort becomes attached the baby and offers to adopt. At first the family agree but when the dead mother's sister, Ola, arrives, she tells Comfort this baby will be her only chance at motherhood since she is HIV. Comfort tearfully says goodbye.
Charlie's suspicions about Mike are confirmed when he phones Sam to check up on his background. Duffy is upset that Charlie went behind her back, but things with Mike are not entirely what they seem. Mike suffers a stroke and as he recovers he reveals to Charlie and Guppy how he was struck off after helping his ill mother die and which is why he is unable to return to the UK. Later alone, Guppy tells Mike how he was in a similar situation with his father but his burden is somewhat lifted when Mike says he regretted the decision he made.
After some heated arguments, Charlie and Duffy finally make peace. Charlie reveals his feelings for Maggie to Duffy, unaware that back in Holby Maggie's relationship with Somnang has taken an unexpected direction when they end up kissing in the staff room. Charlie tells Duffy that he won't be moving out there to help her with the clinic, but will stick around until they get Mike sorted in a hospital in Thailand.
- Main article: Different Worlds - Part Two/Gallery.